U.S. patent number 5,522,532 [Application Number 08/403,616] was granted by the patent office on 1996-06-04 for single-shooting/continuous-shooting control switch for penumatic nail guns.
This patent grant is currently assigned to Testo Industry Corp.. Invention is credited to Jacob Chen.
United States Patent |
5,522,532 |
Chen |
June 4, 1996 |
Single-shooting/continuous-shooting control switch for penumatic
nail guns
Abstract
A single-shooting/continuous-shooting control switch installed
in a pneumatic nail gun for controlling the firing of nails, the
control switch including a first valve seat connected to a
pneumatic pressure source, a second valve seat connected between
the first valve seat and the firing pin of the pneumatic nail gun,
a first valve rod moved by the trigger of the pneumatic nail gun to
control the air passage between the first air valve seat and the
second air valve seat, a second valve rod moved by the trigger of
the pneumatic nail gun to control the air passage between the
second air valve seat and the firing pin, and a stop block turned
about the first valve rod between between a first position for
letting the first valve rod be lifted by the trigger to stop the
passage between the first air passage and the second air passage
for a single-shooting operation, and a second position to stop the
trigger from lifting the first valve rod for letting pneumatic
pressure be continuosuly drawn from the first air valve seat into
the second air valve seat for a continuous shooting operation.
Inventors: |
Chen; Jacob (Taichung,
TW) |
Assignee: |
Testo Industry Corp. (Taichung,
TW)
|
Family
ID: |
23596418 |
Appl.
No.: |
08/403,616 |
Filed: |
March 14, 1995 |
Current U.S.
Class: |
227/8;
227/130 |
Current CPC
Class: |
B25C
1/008 (20130101); B25C 1/04 (20130101) |
Current International
Class: |
B25C
1/00 (20060101); B25C 1/04 (20060101); B25C
001/04 () |
Field of
Search: |
;227/8,120,130 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Smith; Scott A.
Claims
What is claimed is:
1. A single-shooting/continuous-shooting control switch installed
in a pneumatic nail gun for controlling the firing of nails, the
control switch comprising a first air valve seat, a first air
passage for guiding pneumatic pressure from a pneumatic pressure
source into said first air valve seat, a trigger, a first valve rod
moved by said trigger to open and close said first air passage, an
annular stop block fastened to said first air valve seat and turned
about said first valve rod, a second air valve seat, a second air
passage for guding penumatic pressure from said first air valve
seat into said second air valve seat, a second valve rod moved by
said trigger to open and close said second air valve so as to let
penumatic pressure be driven out of said second air valve seat to
drive a firing pin in firing nails out of the pneumatic nail gun,
and wherein said stop block can be turned about said first valve
rod between a first position for letting said first valve rod be
lifted by said trigger to stop the passage between said first air
passage and said second air passage for a single-shooting
operation, and a second position to stop said trigger from lifting
said first valve rod for letting pneumatic pressure be continuosuly
drawn from said first air passage into said second air passage for
a continuous shooting operation.
2. The single-shooting/continuous-shooting control switch of claim
2 wherein said stop block comprises a downward bottom flange
defining a curved bottom hole, said curved bottom hole being
disposed in engagement with one end of said trigger to let-said
first valve rod be lifted by said trigger when said stop block is
turned to said first position, said downward bottom flange being
stopped against said trigger to prohibit said trigger from litling
said first valve rod when said stop block is turned to said second
position.
3. The single-shooting/continuous-shooting control swtich of claim
1 wherein said trigger Comprises a pivot transversely disposed at a
free end thereof, a rotary wheel turned about said pivot, and an
actuating strip having two parallel eyed lugs connected to two
opposite ends of said rotary wheel and turned with said rotary
wheel about said pivot to lift at least one of said first valve rod
and said second valve rod.
Description
BACKGROUND OF THE INVENTION
The present invention to nail gun control swtiches, and relates
more particularly to a single-shooting/continuous-shooting control
switch for nail guns.
Conventional pneumatic nail guns commonly use pnematic pressure to
drive a firing pin in driving nails into workpieces, and a trigger
to control the air passage between the firing pin and the pneumatic
power source. In order to prevent the happening of an error
triggering, a safety is installed in the nail firing head. The
trigger is allowed to drive the valve rod in firing the firing pin
only when the safety is released. As illustrated in FIG. 1A, the
trigger of a regular pneumatic nail gun, referenced by 1, has an
actuating strip 2 stopped at the bottom of the valve rod,
referenced by 31, in a valve seat, referenced by 3. If the trigger
1 is depressed under this condition, the actuating 22 does no work,
and therefore the valve seat 3 is still closed. When the safety,
referenced by 4, at the firing head of the pneumatic nail gun is
stopped against the workpiece as shown in FIG. 1B, the actuating
strip 2 of the trigger i is pushed upwards to lift the valve rod
31, and therefore the air passage through the valve seat 3 to the
firing pin (not shown) is opened for letting pneumatic pressure to
pass and to further drive the firing pin in firing a nail. When the
firing head of the pnematic nail gun is left from the workpiece
fter the firing of a nail, as shown in FIG. 1C, the safety 4 is
lowered to its former position, causing the actuating strip 2 moved
downwards from the valve rod 31, and therefore the valve rod 31
close the air passage to the firing pin again.
Regular penumatic nail guns are commonly gathered into two types,
one for single shooting and one for continuous shooting. When a
pneumatic nail gun is designed for single shooting, only one nail
is driven out of the nail gun each time the trigger is depressed,
and the safety 4 must be removed from the workpiece after each shot
so that the firing mechanism can be reset for a nest firing
operation. When a penumatic nail gun is designed for continuous
shooting, it will fire a rapid and continuous stream of nails when
the trigger is depressed and maintained in the depressed position
and the safety 4 is stopped against the workpiece. However, a
pnematic nail gun for continuous shooting may be driven by an error
to drive nails out of the nail gun, causing nails wasted or even
somebody wounded.
SUMMARY OF THE INVENTION
The present invention has been accomplished under the
circumstances, It is therefore the major object of the present
invention to provide a single-shooting/continuous-shooting control
switch- for pneumatic nail guns which can be conveniently
controlled to set the mode of the nail gun for a single shooting or
a continuous shooting alternatively.
According to one aspect of the present invention, the
single-shooting/continuous-shooting control switch comprises two
air valve seats linked between the penumatic pressure source and
the firing pin, and two valve rods moved by the trigger of the
pneymatic gun to lift the valve rods in controlling the passage
between the penumatic pressure source and the firing pin, and a
stop block turned about one valve rod to let the trigger lift one
valve rod or both valve rods for a continuous shooting operation or
a single shooting operation alternatively.
According to another aspect of the present invention, the stop
block comprises a downward bottom flange defining a curved bottom
hole. The curved bottom hole is disposed in engagement with one end
of the trigger to let both valve rods be lifted by the trigger for
a single shooting operation when the stop block is turned to a
first position. The downward bottom flange is stopped against the
trigger to prohibit the trigger from litfing both valve rods when
the stop block is turned to a second position, and therefore a
continuous shooting operation is allowed.
According to still another aspect of the present invention, the
trigger comprises a pivot transversely disposed at a free end
thereof, a rotary wheel turned about the pivot, and an actuating
strip having two parallel eyed lugs connected to two opposite ends
of the rotary wheel and turned with the rotary wheel about the
pivot to lift one or both valve rods.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a partial view-in plain of a conventional pneumatic nail
gun, showing the relative positions of the trigger, the valve seat
with the valve rod, and the safety;
FIG. 1B is similar to FIG. 1A but showing the safey moved upwards
and the valve rod lifted by the safety;
FIG. 1C is similar to FIG. 1B but showing the safety and the valve
rod moved back to their former positions after the triggering;
FIG. 2 is an exploded view of a part of a
single-shooting/continuous-shooting control switch for pneumatic
nail guns according to the present invention;
FIGS. 3A-3C are drawings of continuous action shwoing the
single-shooting/continuous-shooting control switch of the preferred
embodiment of the present invention installed .in the pneumatic
nail gun and operated under the mode of single-shooting; and
FIGS. 4A-4C are drawings of continuous action showing the
single-shooting/continuous-shooting control switch of the preferred
embodiment of the present invention installed in the penumatic nail
gun and operated under the mode of continuous-shooting.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 2 and 3A, a single-shooting/continuous-shooting
control switch for penumatic nail guns in accordance with the
present invention is generally comprised of a first air valve seat
5, a first valve rod 51 moved in the first air valve seat 5, an
annular stop block 6 fastened to the first air valve seat 5 around
the first valve rod 51, a second air valve seat 7 communicated with
the air passage 501 on the first air valve seat 5 by an air passage
701, a second valve rod 71 moved in the second air valve seat 7, a
trigger 8 pivoted to the shell of the peumatic nail gun and
disposed below the first air valve seat 5 and the second air valve
seat 7 and controlled to move the first valve rod 51 and the second
valve rod 52, an actuating strip 9 pivoted to the trigger 8, a
rotary wheel 91 fastenedf to the actuating strip 9 and the trigger
8, and a safety 10 for a safety control. The annular stop block 6
has a downward bottom flange 61 disposed outside the bottom side of
the first air valve seat 5, defining a curved bottom hole 611. The
actuating strip 9 has two parallel lugs 901 and 901 bilaterally
disposed at one end, each lug defining a pivot hole 902 or 903. The
rotary wheel 91 is stopped between the lugs 901 and 901' and then
the lugs 901 and 901' with the rotary wheel 91 are fastened between
two opposite pin holes 801 on the two parallel upright walls 82 and
82' of the trigger 8 at the rear end by a pivot 81. When installed,
the rotary wheel 91 can be rotated to turn the actuating trip 9
about the pivot 81.
Referring to FIG. 3B, when the strop block 6 is turned about the
first valve rod 51 in one direction through a predetermined angle,
the downward bottom flange 61 of the stop block 6 becomes disposed
in parallel to the actuating strip 9. When the trigger 8 is
depressed during this stage, the rotary wheel 91 is simultaneously
moved upwards and forced into engagement with the curved bottom
hole 611 to further lift the first valve rod 51 in stopping the air
passage 701 from the air passage 501, therefore only a fixed amount
of compressed air is maintained inside the air passage 701 within
the second air valve seat 7, and continuous pneumatic pressure is
stopped from passing through the air passage 501 in the first air
valve seat 5 into the second air valve seat 7. When the safety 10
is stopped against the workpiece to lift the second valve rod 71
after the air passage 701 of the second air valve seat 7 is closed,
the actuating strip 9 is moved to lift the second valve rod 71,
causing the preserved compressed air to escape out of the air
passage 701 of the second air valve seat 7 and to further drive a
nail out of the penumatic nail gun. When the safety 10 is removed
from the workpiece after the firing, as shown in FIG. 3C, the
rotary wheel 91 is maintained in engagement with the curved bottom
hole 611 on the outward flange 61 of the stop block 6, and the
first valve rod 51 is still maintained in the stopped position in
stopping the air passage 701 from the air passage, therefore
continuously depressing the trigger 8 does not cause the firing pin
to work. When the safety 10 is left from the workpiece, second
valve rod 71 of second air valve seat 7 is lowered with the front
end of the actuating strip 9 to the original stand-by position. If
the trigger 8 is maintained depressed and the safety 10 is stopped
against the workpiece during this stage, no nail will be fired
because the first valve rod 51 is still maintained in the stopped
position in stopping the air passage 701 from the air passage 501.
Therefore, the penumatic nail gun can be driven to fire nails again
only when the trigger 8 is released to disconnect the rotary wheel
91 from the stop block 6 for allowing the first valve rod 51 to
open the passage between the air passage 701 and the air passage
501.
For a continuous shooting, please refer to FIGS. 4A and 4B. When
the stop block 6 is turned in the .reversed direction through a
predetermined angle, the downward bottom flange 61 of the stop
block 6 becomes disposed perpendicular to the rotary wheel 91. When
the trigger 8 is depressed during this stage, the downward bottom
flange 61 of the stop block 6 stops the rotary wheel 91 from
lifting the first valve rod 51, and therefore the pneumatic
pressure is allowed to continuously pass from the air passage 501
into the air passage 701. If the safety 10 is stopped against the
workpiece to lift the second valve rod 71, penumatic pressure is
continuously forced out of the second air valve seat 7, causing the
firing pin to fire a rapid and continuous stream of nails out of
the pneumatic gun. When the safety 10 is removed from the
workpiece, as shown in FIG. 4C, the actuating strip 9 and the
second valve rod 71 immediately move to their former positions,
causing the firing pin returned to the standy position. If the
safety 10 is stopped against the workpiece and the trigger 8 is
depressed again, the firing pin is triggered to fire a rapid and
continuous stream of nails again.
It is to be understood that the drawings are designed for purposes
of illustration only, and are not intended as a difinition of the
limits and scope of the invention disclosed.
* * * * *